From: E S <eero.saynatkari@...>
Date: 2005-01-18T09:07:45+09:00
Subject: Re: Fwd: [suby-ruby] Your all time desired fundemental Ruby mod

> L�hett�j�: Yukihiro Matsumoto <matz@ruby-lang.org>
> Aihe: Re: Fwd: [suby-ruby] Your all time desired fundemental Ruby mod
> 
> Hi,
> 
> In message "Re: Fwd: [suby-ruby] Your all time desired fundemental Ruby mod"
>     on Mon, 17 Jan 2005 23:22:30 +0900, "trans.  (T. Onoma)" <transami@runbox.com> writes:
> 
> |I want to expand the functionality of this class with a module I have:
> |
> |  module M
> |    def x ; @x ; end
> |  end
> |
> |But @x needs to default to an array. So what do I do? Presently I have two 
> |choices. Either change M to:
> |
> |  module M
> |    def x ; @x ||= [] ; end
> |  end
> |
> |or use super as you suggest. But I don;t want to just recopy C for what if it 
> |changed internally later?
> 
> Initializing module instance variables are one of the things I want to
> fix.  But I'm not sure what is the best way to fix.  Maybe AOP-like
> hooks is the way to go.  I'm waiting the conviction to come.

Does it need to be fixed? I don't think instance variables belong in
a Module, conceptually. They can be put there, yes, it's just harder
to get them in proper working order, which encourages 'proper' design
but allows circumvention if necessary. I can't think of any situations
where one would have no other option than instance variables in a 
Module.

> 							matz.

E